stop reloading dropdowns after add - jqgrid

Question

Here is the code of my dropdown.
{
name: 'ClassId', index: 'ClassId', align: 'center',editable: true, edittype: 'select',
editoptions: {
dataUrl:'#Url.Action("GetAllClasses", "Class", new { Area = "Curriculums"})',
buildSelect: function (data) {
var response, s = '<select>', i;
response = jQuery.parseJSON(data);
//s += '<option value="0">--Select Class--</option>';
if (response && response.length) {
$.each(response, function (i) {
s += '<option value="' + this.Id + '">' + this.ClassName + '</option>';
});
}
return s + '</select>';
}
}
},
I am using form edit.I am reloading grid after insert.But the problem is after inserting data when I try to add another one my dropdowns are getting refreashed.I want that the dropdown selected value will be previously selected value.I don't want to change dropdown selected value on the second add.

Answer 1

The most simple way to prevent reloading of data from dataUrl could be setting Cache-Control HTTP header in the server response. Setting of Cache-Control: max-age=60 in the server response for example will prevent reloading of data from the server during 60 sec. In case of ASP.NET MVC you can use CacheControl attribute for example (see Duration and Location properties).
One more alternative would be dynamical setting editoptions.value instead of usage editoptions.dataUrl. For example one can include the information needed for building editoptions.value as an extension of the standard response of the server for filling the grid. One can use beforeProcessing to process the part of the data. You will find the corresponding examples in the following cold answers: this one, this one, this one, this one, this one and other. The answer describes in short one of the the possible scenario to create full dynamic grid.